The present invention relates to implant devices and, in particular, relates to implant devices for retaining dentures.
Unsatisfactory dentures have presented a continual problem to the patient and dentist. In the past, dentures were retained in place in the mouth on the edentulous ridges by two forces, a peripheral seal which produced a partial vacuum and an interfacial surface tension which involved an intimate fit of tissue to the surface of the denture aided by a film of saliva. With aging and disease of the alveolar bones of the maxilla and mandible, the edentulous ridges progressively atrophied. With atrophication and reabsorption of bony tissues of the edentulous ridges, the ridges were incapable of effectively retaining dentures. The dentures were easily dislodged with mastication, speech and all other oral functions. Recurrent soreness of the mouth tissues ensued and adjusting the remaking the dentures did not solve the problem.
Several prior methods have been utilized to aid denture retention. Firstly, denture adhesives have been utilized. Unfortunately, denture adhesives rapidly deteriorate thereby losing their effectiveness and becoming unhygienic. Secondly, full subperiosteal implant devices have also been used to retain dentures. The arch-shaped device consisted of a metal such as vitallium and was implanted into the mouth below the periosteum. The device was secured by screws and was provided with four abutment posts which protruded through the mucosa to serve as a point of attachment for the dentures. The dentures were provided with retaining clasps which were clipped onto the abutment posts. Unfortunately, the procedure for implanting the device required two radical surgical procedures and therefore was not suitable for many patients. Lastly, intra-boney implant devices have been utilized to retain dentures. The metallic devices were inserted into the alveolar bone and functioned as abutments for the dentures. The devices were fabricated in the form of blades which were tapped into place in a trench cut in the alveolar bone, screws which were secured into the alveolar bone with a ratchet wrench and a tripod of pins which were inserted into the alveolar bone. Unfortunately, in many cases, the foreign body reaction of the bone to the metallic implant resulted in pain, bone destruction, infection and rejection of the implant thereby necessitating the subsequent removal of the implant.